/**
 * Copyright 2009-2020 the original author or authors.
 * <p>
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.ibatis.annotations;

import java.lang.annotation.*;

/**
 * The annotation that specify a method that provide an SQL for inserting record(s).
 *
 * <p>
 * <b>How to use:</b>
 *
 * <pre>
 * public interface UserMapper {
 *
 *   &#064;InsertProvider(type = SqlProvider.class, method = "insert")
 *   void insert(User user);
 *
 *   public static class SqlProvider {
 *     public static String insert() {
 *       return "INSERT INTO users (id, name) VALUES(#{id}, #{name})";
 *     }
 *   }
 *
 * }
 * </pre>
 *
 * @author Clinton Begin
 */
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@Repeatable(InsertProvider.List.class)
public @interface InsertProvider {

	/**
	 * Specify a type that implements an SQL provider method.
	 *
	 * @return a type that implements an SQL provider method
	 * @since 3.5.2
	 * @see #type()
	 */
	Class<?> value() default void.class;

	/**
	 * Specify a type that implements an SQL provider method.
	 * <p>
	 * This attribute is alias of {@link #value()}.
	 * </p>
	 *
	 * @return a type that implements an SQL provider method
	 * @see #value()
	 */
	Class<?> type() default void.class;

	/**
	 * Specify a method for providing an SQL.
	 *
	 * <p>
	 * Since 3.5.1, this attribute can omit.
	 * If this attribute omit, the MyBatis will call a method that decide by following rules.
	 * <ul>
	 *   <li>
	 *     If class that specified the {@link #type()} attribute implements the
	 *     {@link org.apache.ibatis.builder.annotation.ProviderMethodResolver},
	 *     the MyBatis use a method that returned by it
	 *   </li>
	 *   <li>
	 *     If cannot resolve a method by {@link org.apache.ibatis.builder.annotation.ProviderMethodResolver}(= not implement it or it was returned {@code null}),
	 *     the MyBatis will search and use a fallback method that named {@code provideSql} from specified type
	 *   </li>
	 * </ul>
	 *
	 * @return a method name of method for providing an SQL
	 */
	String method() default "";

	/**
	 * @return A database id that correspond this provider
	 * @since 3.5.5
	 */
	String databaseId() default "";

	/**
	 * The container annotation for {@link InsertProvider}.
	 * @author Kazuki Shimizu
	 * @since 3.5.5
	 */
	@Documented
	@Retention(RetentionPolicy.RUNTIME)
	@Target(ElementType.METHOD)
	@interface List {
		InsertProvider[] value();
	}

}
